There's a certain thin range of voltage that is bad for BMWs where the
instrument cluster goes haywire, and that voltage is in the opposite of
the Goldilocks Zone.

That is, instead of it being not too hot and not too cold, which would be
a good thing for a Goldilocks Zone... the voltage is just a tad not low
enough to cause the car not to start but just low enough to cause the
instrument cluster to go haywire.